/src/dropbear/src/dbmalloc.c

Source
#include "dbmalloc.h"
#include "dbutil.h"


void * m_calloc(size_t nmemb, size_t size) {
    if (SIZE_T_MAX / nmemb < size) {
        dropbear_exit("m_calloc failed");
    }
    return m_malloc(nmemb*size);
}

void * m_strdup(const char * str) {
    char* ret;
    unsigned int len;
    len = strlen(str);

    ret = m_malloc(len+1);
    if (ret == NULL) {
        dropbear_exit("m_strdup failed");
    }
    memcpy(ret, str, len+1);
    return ret;
}

#if !DROPBEAR_TRACKING_MALLOC

/* Simple wrappers around malloc etc */
void * m_malloc(size_t size) {

  void* ret;

  if (size == 0) {
    dropbear_exit("m_malloc failed");
  }
  ret = calloc(1, size);
  if (ret == NULL) {
    dropbear_exit("m_malloc failed");
  }
  return ret;

}

void * m_realloc(void* ptr, size_t size) {

  void *ret;

  if (size == 0) {
    dropbear_exit("m_realloc failed");
  }
  ret = realloc(ptr, size);
  if (ret == NULL) {
    dropbear_exit("m_realloc failed");
  }
  return ret;
}


#else

/* For fuzzing */

struct dbmalloc_header {
    unsigned int epoch;
    struct dbmalloc_header *prev;
    struct dbmalloc_header *next;
};

static void put_alloc(struct dbmalloc_header *header);
static void remove_alloc(struct dbmalloc_header *header);

/* end of the linked list */
static struct dbmalloc_header* staple;

unsigned int current_epoch = 0;

void m_malloc_set_epoch(unsigned int epoch) {
    current_epoch = epoch;
}

void m_malloc_free_epoch(unsigned int epoch, int dofree) {
    struct dbmalloc_header* header;
    struct dbmalloc_header* nextheader = NULL;
    struct dbmalloc_header* oldstaple = staple;
    staple = NULL;
    /* free allocations from this epoch, create a new staple-anchored list from
    the remainder */
    for (header = oldstaple; header; header = nextheader)
    {
        nextheader = header->next;
        if (header->epoch == epoch) {
            if (dofree) {
                free(header);
            }
        } else {
            header->prev = NULL;
            header->next = NULL;
            put_alloc(header);
        }
    }
}

static void put_alloc(struct dbmalloc_header *header) {
    assert(header->next == NULL);
    assert(header->prev == NULL);
    if (staple) {
        staple->prev = header;
    }
    header->next = staple;
    staple = header;
}

static void remove_alloc(struct dbmalloc_header *header) {
    if (header->prev) {
        header->prev->next = header->next;
    }
    if (header->next) {
        header->next->prev = header->prev;
    }
    if (staple == header) {
        staple = header->next;
    }
    header->prev = NULL;
    header->next = NULL;
}

static struct dbmalloc_header* get_header(void* ptr) {
    char* bptr = ptr;
    return (struct dbmalloc_header*)&bptr[-sizeof(struct dbmalloc_header)];
}

void * m_malloc(size_t size) {
    char* mem = NULL;
    struct dbmalloc_header* header = NULL;

    if (size == 0 || size > 1e9) {
        dropbear_exit("m_malloc failed");
    }

    size = size + sizeof(struct dbmalloc_header);

    mem = calloc(1, size);
    if (mem == NULL) {
        dropbear_exit("m_malloc failed");
    }
    header = (struct dbmalloc_header*)mem;
    put_alloc(header);
    header->epoch = current_epoch;
    return &mem[sizeof(struct dbmalloc_header)];
}

void * m_realloc(void* ptr, size_t size) {
    char* mem = NULL;
    struct dbmalloc_header* header = NULL;
    if (size == 0 || size > 1e9) {
        dropbear_exit("m_realloc failed");
    }

    header = get_header(ptr);
    remove_alloc(header);

    size = size + sizeof(struct dbmalloc_header);
    mem = realloc(header, size);
    if (mem == NULL) {
        dropbear_exit("m_realloc failed");
    }

    header = (struct dbmalloc_header*)mem;
    put_alloc(header);
    return &mem[sizeof(struct dbmalloc_header)];
}

void m_free_direct(void* ptr) {
    struct dbmalloc_header* header = NULL;
    if (!ptr) {
        return;
    }
    header = get_header(ptr);
    remove_alloc(header);
    free(header);
}

#endif /* DROPBEAR_TRACKING_MALLOC */

void * m_realloc_ltm(void* ptr, size_t oldsize, size_t newsize) {
   (void)oldsize;
   return m_realloc(ptr, newsize);
}

void m_free_ltm(void *mem, size_t size) {
   (void)size;
   m_free_direct(mem);
}

Line	Count	Source
1		#include "dbmalloc.h"
2		#include "dbutil.h"
3
4
5	0	void * m_calloc(size_t nmemb, size_t size) {
6	0	if (SIZE_T_MAX / nmemb < size) {
7	0	dropbear_exit("m_calloc failed");
8	0	}
9	0	return m_malloc(nmemb*size);
10	0	}
11
12	12	void * m_strdup(const char * str) {
13	12	char* ret;
14	12	unsigned int len;
15	12	len = strlen(str);
16
17	12	ret = m_malloc(len+1);
18	12	if (ret == NULL) {
19	0	dropbear_exit("m_strdup failed");
20	0	}
21	12	memcpy(ret, str, len+1);
22	12	return ret;
23	12	}
24
25		#if !DROPBEAR_TRACKING_MALLOC
26
27		/* Simple wrappers around malloc etc */
28		void * m_malloc(size_t size) {
29
30		void* ret;
31
32		if (size == 0) {
33		dropbear_exit("m_malloc failed");
34		}
35		ret = calloc(1, size);
36		if (ret == NULL) {
37		dropbear_exit("m_malloc failed");
38		}
39		return ret;
40
41		}
42
43		void * m_realloc(void* ptr, size_t size) {
44
45		void *ret;
46
47		if (size == 0) {
48		dropbear_exit("m_realloc failed");
49		}
50		ret = realloc(ptr, size);
51		if (ret == NULL) {
52		dropbear_exit("m_realloc failed");
53		}
54		return ret;
55		}
56
57
58		#else
59
60		/* For fuzzing */
61
62		struct dbmalloc_header {
63		unsigned int epoch;
64		struct dbmalloc_header *prev;
65		struct dbmalloc_header *next;
66		};
67
68		static void put_alloc(struct dbmalloc_header *header);
69		static void remove_alloc(struct dbmalloc_header *header);
70
71		/* end of the linked list */
72		static struct dbmalloc_header* staple;
73
74		unsigned int current_epoch = 0;
75
76	245	void m_malloc_set_epoch(unsigned int epoch) {
77	245	current_epoch = epoch;
78	245	}
79
80	245	void m_malloc_free_epoch(unsigned int epoch, int dofree) {
81	245	struct dbmalloc_header* header;
82	245	struct dbmalloc_header* nextheader = NULL;
83	245	struct dbmalloc_header* oldstaple = staple;
84	245	staple = NULL;
85		/* free allocations from this epoch, create a new staple-anchored list from
86		the remainder */
87	4.91k	for (header = oldstaple; header; header = nextheader)
88	4.67k	{
89	4.67k	nextheader = header->next;
90	4.67k	if (header->epoch == epoch) {
91	1.24k	if (dofree) {
92	1.24k	free(header);
93	1.24k	}
94	3.43k	} else {
95	3.43k	header->prev = NULL;
96	3.43k	header->next = NULL;
97	3.43k	put_alloc(header);
98	3.43k	}
99	4.67k	}
100	245	}
101
102	4.72k	static void put_alloc(struct dbmalloc_header *header) {
103	4.72k	assert(header->next == NULL);
104	4.72k	assert(header->prev == NULL);
105	4.72k	if (staple) {
106	4.48k	staple->prev = header;
107	4.48k	}
108	4.72k	header->next = staple;
109	4.72k	staple = header;
110	4.72k	}
111
112	28	static void remove_alloc(struct dbmalloc_header *header) {
113	28	if (header->prev) {
114	18	header->prev->next = header->next;
115	18	}
116	28	if (header->next) {
117	28	header->next->prev = header->prev;
118	28	}
119	28	if (staple == header) {
120	10	staple = header->next;
121	10	}
122	28	header->prev = NULL;
123	28	header->next = NULL;
124	28	}
125
126	28	static struct dbmalloc_header* get_header(void* ptr) {
127	28	char* bptr = ptr;
128	28	return (struct dbmalloc_header*)&bptr[-sizeof(struct dbmalloc_header)];
129	28	}
130
131	1.29k	void * m_malloc(size_t size) {
132	1.29k	char* mem = NULL;
133	1.29k	struct dbmalloc_header* header = NULL;
134
135	1.29k	if (size == 0 \|\| size > 1e9) {
136	0	dropbear_exit("m_malloc failed");
137	0	}
138
139	1.29k	size = size + sizeof(struct dbmalloc_header);
140
141	1.29k	mem = calloc(1, size);
142	1.29k	if (mem == NULL) {
143	0	dropbear_exit("m_malloc failed");
144	0	}
145	1.29k	header = (struct dbmalloc_header*)mem;
146	1.29k	put_alloc(header);
147	1.29k	header->epoch = current_epoch;
148	1.29k	return &mem[sizeof(struct dbmalloc_header)];
149	1.29k	}
150
151	0	void * m_realloc(void* ptr, size_t size) {
152	0	char* mem = NULL;
153	0	struct dbmalloc_header* header = NULL;
154	0	if (size == 0 \|\| size > 1e9) {
155	0	dropbear_exit("m_realloc failed");
156	0	}
157
158	0	header = get_header(ptr);
159	0	remove_alloc(header);
160
161	0	size = size + sizeof(struct dbmalloc_header);
162	0	mem = realloc(header, size);
163	0	if (mem == NULL) {
164	0	dropbear_exit("m_realloc failed");
165	0	}
166
167	0	header = (struct dbmalloc_header*)mem;
168	0	put_alloc(header);
169	0	return &mem[sizeof(struct dbmalloc_header)];
170	0	}
171
172	30	void m_free_direct(void* ptr) {
173	30	struct dbmalloc_header* header = NULL;
174	30	if (!ptr) {
175	2	return;
176	2	}
177	28	header = get_header(ptr);
178	28	remove_alloc(header);
179	28	free(header);
180	28	}
181
182		#endif /* DROPBEAR_TRACKING_MALLOC */
183
184	0	void * m_realloc_ltm(void* ptr, size_t oldsize, size_t newsize) {
185	0	(void)oldsize;
186	0	return m_realloc(ptr, newsize);
187	0	}
188
189	0	void m_free_ltm(void *mem, size_t size) {
190	0	(void)size;
191	0	m_free_direct(mem);
192	0	}

Coverage Report

Created: 2026-09-01 06:28